Attachment metal fitting for detachable bridge dentures



June 12, 1928. T 1,673,286

K. INOUE ATTACHMENT METAL FITTING FOR DETACHABLE BRIDGE DENTURES Filed July 7, 1926 Fz I Fag 4L 6 Z A (YE;

fig a Dwenfor: Kojiro Ihoue By my, 0am, 17am W Hi5 Affomeus.

Patented June 12, 1928.

UNITED STATES KOJIRO' menu, or ToKYo, JAPAN.

ATTACHMENT METAL- EITTING FOR DETACfiABLE BRIDGE DENTURES;

Application filed July 7, 1926, Serial No. 120,904, a1ul. in Japan May 11, 192.6."

This invention relatesto attachment metal fittings for detachable bridge denture, consisting of a gapped ring to be fixed to an abutment tooth and an angled stem to be attached to a detachable bridge denture. The angled stem is provided near its one end with a projection which has fiat surfaces on twoopposite sides to allow it to pass. through the gap, and which has peripheral surfaceson the other two opposite sides to cause it to be fitted, when revolved, into the inner surface of the ring. On the angled stem, two bands having a common strut, are pivoted with the projection between them, which bandsand projection are to be fixed in the gutta percha base of a detachable. bridge denture.

The object of this invention is'to simplify and facilitate the working on an abutment tooth and the manufacturing of a detachable bridge denture; to ensure the attachment of the said bridge denture so as to perfectly prevent the abutment toothfrom being detached by sticky food; and'in case of a detachable bridge denture having an abutment tooth on one side, to moderate the stress on the abutment tooth caused-by mastication.

Referring to the accompanying drawings,

Fig. 1 is a front elevation of my invention in which the projection of the angled stem is inserted in the gapped ring,

Fig. 2, the plan of the above,

Fig. 3, the back elevation of same,

Fig. 4, the plan of the angled stem,

Fig. 5, the elevation of the above,

Fig. 6, the sectional view on line XX of Fig. 2,

Fig. 7, the sectional view of my invention in which the angled stem is put in such a po-' sition as to be taken out of the ring through the s p Fig. 8, the elevation of an abutment tooth with a gapped ring attached thereto,

Fig. 9, the elevation of the detachable bridge denture with the angled stem fixed thereto and the projection placed in such a position as to be able to pass through the -s p,

Fig. 10, the elevation of the-detachable bridge denture, the projection of the angled stein being fitted to the inner surface of the gapped ring,

Fig. 11, a detachable bridge denture having an abutment tooth on one side only.

As shown in the accompanying drawings, my invention consists of a grapped-ring (1) and an angled stem (2). The angled stem jection (4) having flat surfaces on opposite sides-to let it pass through the ring-gap (3),

and peripheral surfaces on the other two opposite sides to fit it in the inner surface of the gapped ring (1). On the angled stem (2), two bands (6), (6) having a common strut (5) are pivoted with the projection (4) bet'ween'them. j I

The projection (4), when revolved by the external arm (7 of the angled stem (2), is inserted into or taken out of the gapped ring (1). The gapped ring (l), as shown in Fig, 8 is fixed directly'or by means of a, washer (8), to the abutment tooth (9). The angled stem, as in Figs. 9 and 10, fixed tothe detachable bridge denture by fixing, the. strut (5) and the bands (6), (6) in the body of the gutta percha'base (10) of the bridge. denture, the projection (4) being situated in the cavity (11) of the gutta percha base. (10). When the external arm (7) of the angled stem (2) is lifted and the bridge denture (10) is pressed against the abutment tooth (9 the projection (4) will pass through the gap into the ring Then, when the external arm (7) is laid down, the projection (,4) will be revolved and fitted in the inner surface of the gapped ring (1) and at the same time the external arm (7 hold the abutment tooth (9) fast ment'tooth simply by lifting the external arm (7') with fingers and picking it up.

The superiority of detachable bridge dentures over the partial denture with base and the'fixed bridge denture is generally known, but the complexity and difliculty inmanufacturing it and the devitalization in many cases of abutment teeth are also known as the chief defects of detachable bridge works. For instance, the detachable bridge work endsin failure on account of a trifling mistake made in design or working as to the mutualrelation between the attachment arrangements on both sides-of a detachable bridge denture; and, on account of necessity of making parallel the confronting surfaces on the bridge denture and the abutment tooth or the confronting surfaces on abutment teeth, those abutment teeth are often devitalized. In my invention, however, the

iv I) ring-gap (3), through which the projection (4) on the angled stem passes, may be made comparatively larger without decreasingthe firmness of attachment of the 1 detachable bridge denture, the attachment being made by revolving the projection (4), thereby to fit it in the inner surface of the gapped ring Again, as" the gapped-ring (1) has a short centerline and the ring-gap :(3) Y may be made comparat vely larger as above described, the accuracy of the innersurface,

in the gapped ring and the peripheral surfaces on the projection (4;) is enough for V 'the firmness of attachment, but accuracyjin design andworking is notneces'sary as is in detachable bridge works hitherto known;

Moreover, theconfronting surfacesjon the v detachable bridge denture and the abutment teeth need not bemade parallel, and therefore the troubles hitherto caused by "complexity and difiicultyin the manufacture of. .detachablebridge dentures and the de- 'vitalization of abutment teeth have been removed. V M V The angledstem (2) is inserted from out-r sidein. the detachable bridge denture and the strut -(5), and the bands (.6), .(6) are i fixed in the body of the gutta percha. base (10) of the idetachablebridgedenture, thus giving stability to the angled stem (2). Thebands (6), v,(6) fill up the gap between the angled stem (2) and the body, of the;

\ guttapercha base (10) which not only gives stability to the angled stem (2), but also prevents the gutta perchav base (10).. from' wearing/ out by the friction caused by the revolution of the angled stem (2);,

If the metal fittings of my invention are" used for a detachable bridge denturelwhi ch has an abutment tooth on one side only, the

detachable bridge denture, in mastication,

j presses the elastic alveolar membrane with the angled stem as an axis, and makes an; oscillatory motion, so that the stress caused by masticationacts mainly upon the alveolar membrane and the stress upon the abutment ture.

tooth is considerably moderated, in consequence of which the damaging of the abutment tooth is greatly reduced. The reduc-' tion of-s'tress upon the abutment tooth will be secured most efi'ectively, by fixing the gapped ring (I) to the abutment tooth in "contact with the gum, and fixing the angled stem to the detachable bridge denture inthe proper situation as shown in Fig. 11.

said invention, what I claim to be protected .by Letters Patent is 314A fitting for a detachable bridge deniture, consisting of a gapped ring to be fixed to an abutment tooth, and a. rotary'stem fitted to the detachable bridge denture, said Having now particularly described my rotary stem being provided near. one end.

with a projection having a flat surface on OIIGHSIQlQ so as to allow it to pass through the gapiin said ring, andperipheral sur-' jection, when rotated, to fit against the inner surface of the gapped ring, and two bands haying a common strutfixed to the .base of. said denture, said stein being pivoted to the tween.

2. a fitting for adetachable bridge den-' ,ture, comprisin a gapped ring adapted to be fixed, tov an abutmenttooth, and a rotary stem adapted to be fitted to the denture,-said rotary stem being providednear one end with a projection having'fiat surfaces on two opposite sides so as to allow it to pass faces on thebther sides to cause said probands with tl1e projection 'therebe- "through the gap in said ring, and peripheral surfaces on the-other two opposite sides to causethe projection, when rotated, to fit 

